Impact resistant materials (high impact- and notch impact strength) for especially highly stressed engine blading. If this is not sufficiently safely possible (for example, in fan stators), one may consider materials such as fiber-reinforced synthetics, which may fracture, but will only cause minor consequential damages.
Use of thickest possible blade profiles with the maximum thickness located towards the leading edge, rounded leading and trailing edges, and short aspect ratio; these demands do not correspond to the geometry of modern compressor blades with wide chords and supersonic profiles. Despite this, the demands posed by bird strikes should be given as much consideration as possible.
Wide spacing between stages, tightly spaced blades.
Bracing long, slender (fan) blades with clappers, if possible set on alternating sides to further improve the (slicing effect) bird strike resistance
Resilient, heavily damped rotor blade fastening
Stator blades/vanes that are as stiff as possible and fastened together in rings or ring segments
Hollow (e.g. for de-icing air) guide vanes should be designed to prevent buckling, through use of stiffening spars and a non-bursting trailing edge.
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Carefully designing inner bearings and bearing connections of adjustable guide vanes.
Predetermined break points should prevent closing and blocking of the blades in case of extreme overloading of the guide blade adjustment levers.
Burst protection rings above fan rotor blades.
Sufficient ring-reinforcements on the compressor casings to prevent bursting.
Preventing large amounts of flammable dusts from being created due to imbalances cause by bird strikes; no flammable rub-tolerant coatings and blade materials in potential contact areas.
If there is a risk of high-speed direct hits, there should be no inlet stator annulus or housing/casing struts ahead of the first rotor stage.
Avoiding swan-neck air ducts, including in the rear compressor area. If a swan-neck duct is unavoidable, at the least the first rotor blading immediately following the duct must be especially robust in order to prevent overstressing due to collected bird pieces.
Air extraction bores and slits (vents, for cabin air, de-icing air, cooling air, etc.) should be designed in such a way that they will not become blocked.
Rotor disk connections and rotor shaft teeth should be designed to be shear-proof in case of polar weight moments of inertia.
With bladings made from titanium alloys, the ignition of titanium fires as consequential damage after a bird strike should be minimized through suitable pairing of materials (rub coatings) on potential rub surfaces.
Rotor disks should be sufficiently solid near the annulus to prevent the annulus breaking off due to the high loads caused by a bird strike.